A riser device
CA 2402779 A1 · Owner: National Oilwell Norway As · Inventors: Gjedebo, Jon Grude
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A riser (18) extends between a surface vessel e.g. a drillship (16), and an , item of subsea equipment e.g. a blowout preventer valve (12) on the seabed (10). The riser (18) is equipped with at least one thruster for instance in , the form of one or more motor driven positional propellers (201 202), which , is arranged so as to be able to exert an essentially horizontal thrust force on the riser (18) in order to counteract the lateral forces from the oceanic currents, so as to maintain the riser (18) in a position that corresponds to the desired course from the surface vessel (16) to the subsea equipment (12).
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed March 20, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 20, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 20, 2022.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.